content: /* ===========================================================
   * JFreeChart : a free chart library for the Java(tm) platform
   * ===========================================================
   *
   * (C) Copyright 2000-2012, by Object Refinery Limited and Contributors.
   *
   * Project Info:  http://www.jfree.org/jfreechart/index.html
   *
   * This library is free software; you can redistribute it and/or modify it
   * under the terms of the GNU Lesser General Public License as published by
   * the Free Software Foundation; either version 2.1 of the License, or
   * (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
   * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
   * License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
   * USA.
   *
   * [Oracle and Java are registered trademarks of Oracle and/or its affiliates.
   * Other names may be trademarks of their respective owners.]
   *
   * -----------------------------
   * MeanAndStandardDeviation.java
   * -----------------------------
   * (C) Copyright 2003-2012, by Object Refinery Limited.
   *
   * Original Author:  David Gilbert (for Object Refinery Limited);
   * Contributor(s):   -;
   *
   * Changes:
   * --------
   * 05-Feb-2002 : Version 1 (DG);
   * 05-Feb-2005 : Added equals() method and implemented Serializable (DG);
   * 02-Oct-2007 : Added getMeanValue() and getStandardDeviationValue() methods
   *               for convenience, and toString() method for debugging (DG);
   * 17-Jun-2012 : Removed JCommon dependencies (DG);
   *
   */
  
  package org.jfree.data.statistics;
  
  import java.io.Serializable;
  
  import org.jfree.chart.util.ObjectUtilities;
  
  /**
   * A simple data structure that holds a mean value and a standard deviation
   * value.  This is used in the
   * {@link org.jfree.data.statistics.DefaultStatisticalCategoryDataset} class.
   */
  public class MeanAndStandardDeviation implements Serializable {
  
      /** For serialization. */
      private static final long serialVersionUID = 7413468697315721515L;
  
      /** The mean. */
      private Number mean;
  
      /** The standard deviation. */
      private Number standardDeviation;
  
      /**
       * Creates a new mean and standard deviation record.
       *
       * @param mean  the mean.
       * @param standardDeviation  the standard deviation.
       */
      public MeanAndStandardDeviation(double mean, double standardDeviation) {
          this(Double.valueOf(mean), Double.valueOf(standardDeviation));
      }
  
      /**
       * Creates a new mean and standard deviation record.
       *
       * @param mean  the mean (<code>null</code> permitted).
       * @param standardDeviation  the standard deviation (<code>null</code>
       *                           permitted.
       */
      public MeanAndStandardDeviation(Number mean, Number standardDeviation) {
          this.mean = mean;
          this.standardDeviation = standardDeviation;
      }
  
      /**
       * Returns the mean.
       *
       * @return The mean.
       */
      public Number getMean() {
          return this.mean;
      }
  
      /**
       * Returns the mean as a double primitive.  If the underlying mean is
       * <code>null</code>, this method will return <code>Double.NaN</code>.
       *
       * @return The mean.
       *
       * @see #getMean()
       *
       * @since 1.0.7
       */
      public double getMeanValue() {
          double result = Double.NaN;
          if (this.mean != null) {
              result = this.mean.doubleValue();
          }
          return result;
      }
  
      /**
       * Returns the standard deviation.
       *
       * @return The standard deviation.
       */
      public Number getStandardDeviation() {
          return this.standardDeviation;
      }
  
      /**
       * Returns the standard deviation as a double primitive.  If the underlying
       * standard deviation is <code>null</code>, this method will return
       * <code>Double.NaN</code>.
       *
       * @return The standard deviation.
       *
       * @since 1.0.7
       */
      public double getStandardDeviationValue() {
          double result = Double.NaN;
          if (this.standardDeviation != null) {
              result = this.standardDeviation.doubleValue();
          }
          return result;
      }
  
      /**
       * Tests this instance for equality with an arbitrary object.
       *
       * @param obj  the object (<code>null</code> permitted).
       *
       * @return A boolean.
       */
      @Override
      public boolean equals(Object obj) {
          if (obj == this) {
              return true;
          }
          if (!(obj instanceof MeanAndStandardDeviation)) {
              return false;
          }
          MeanAndStandardDeviation that = (MeanAndStandardDeviation) obj;
          if (!ObjectUtilities.equal(this.mean, that.mean)) {
              return false;
          }
          if (!ObjectUtilities.equal(
              this.standardDeviation, that.standardDeviation)
          ) {
              return false;
          }
          return true;
      }
  
      /**
       * Returns a string representing this instance.
       *
       * @return A string.
       *
       * @since 1.0.7
       */
      @Override
      public String toString() {
          return "[" + this.mean + ", " + this.standardDeviation + "]";
      }
  
  }